The preparation of oil-in-water emulsion based compositions is generally known to the art, but not in the context of their use in preparing a clear low residue antiperspirant composition.
Over the years various workers in the field have attempted to create enhanced antiperspirant emulsion compositions using a variety of ingredients in various combinations all of which have been found to be limited in one respect or another. Amongst the prior art references relating to this area of which the applicant is aware, are the following:
U.S. Pat. No. 4,788,001 to Narula broadly discloses stable oil-in-water emulsion based compositions as containing an oil, water, and a nonionic three-component emulsifying system, each nonionic surfactant being present in stated concentrations and having a specific HLB requirement. While antiperspirant compositions are not specifically taught by this reference, Narula suggests that the oil-in-water emulsions taught there may find utility in antiperspirant compositions.
U.S. Pat. No. 4,264,586, which issued to Callingham discloses an antiperspirant emulsion composition containing an antiperspirant active, a wax, polydimethylsiloxane, water and an emulsifier.
Witco Tech. Bull. Formula 101A is directed to a clear microemulsion antiperspirant composition containing a mixture of various nonionic surfactants. The composition has a viscosity of 500-5000 cps, and is stable at elevated temperatures.
U.S. Pat. No. 4,499,069 to Krafton is directed to a specific emulsifier system containing PEG (21) stearyl ether.
The foregoing prior art references do not teach or even suggest the totality of the composition of the present invention, nor its equivalents. Further, the known prior art lacks any specific teaching as to the benefits to be achieved by utilizing the particular combination of basic ingredients taught by the applicant herein in order to achieve a clear low residue antiperspirant composition.